Poison oak is a woody vine or shrub that is often used in habitat restoration endeavors. It serves as a nurse plant for other species.
It is famous for the skin rash it causes. It has a sticky oil, called urushiol, surrounding it. Urushiol is a yellow liquid that turns black when it comes in contact with oxygen after it seeps out of the plant. It renders a dull, waxy sheen appearance on poison oak plants. When skin comes in contact with this oil, it causes allergic contact dermatitis. It is a red, itchy rash that causes itching, general redness of the skin, or the appearance of red streaks. It may also cause hives, which are small bumps or large raised areas. Another symptom is blisters that may secrete fluid. This is the most common skin problem that is caused by contact with poisonous plants.
This skin problem is caused by contact with the oil, through any part of the plant. These parts include leaves, flowers, berries, stems and roots. An allergic reaction may occur even if the plant is dead. Urushiol oil can stay potent for as long as five years. If the oil has been transferred to another agent, getting in contact with this material will also cause a rash. Examples of surfaces that may get in contact with urushiol are clothing, pet fur, gardening tools, and sporting gear.
Poison oak varies greatly in appearance. It can grow as dense, tall shrubs in open sunlight, a tree-like vine up to 100 feet long with thick trunks, or as dense thickets in shaded areas. It could also grow as any condition in between these three extremes.
It is most easily identifiable by its leaves. These are usually divided into three leaflets. They resemble the leaves of an oak tree, but glossier. These leaves first unfold around February and March, appearing to be typically bronze. They are bright green during spring. In the summer, the leaves of poison oak are yellow-green to reddish in color, and bright red or pink from late July to October.
After winter, the stems become leafless and bare, making it difficult to identify. They bear only few clusters of berries. A distinguishable mark could be occasional black spots, which could be the urushiol oil that oozed and dried. The stems also give off a greyish tint, although this might be difficult to see given that light is a challenge in forested areas. However, you may notice tiny hair or thorn-like features on the stem.
Poison oak also grows small yellowish-green flowers in the spring, and light green berries all throughout summer and fall.
3 What is a poison oak rash?
Poison oak rash, or allergic contact dermatitis, is contracted when skin comes in contact with urushiol oil. This is an oil produced by poison oak, as well as poison ivy and poison sumac. It causes a red itchy rash that leads to itching, the appearance of red streaks, general redness of the skin, hives and blisters.
The rash is contracted and spread only through the oil. You cannot get the rash by touching someone with the rash, or by coming into contact with the blister fluids.
However, the rash is not an immediate reaction. Symptoms of the rash could take over a week to show up the first time. It may be difficult to tell that the rash came from poison ivy. On succeeding contacts, the reaction speeds up to a day or two.
The rash lasts anywhere from 10 days to three weeks. At its most severe, it could take up to six weeks to heal. In some people, the allergic reaction is stronger. This can begin with mere skin symptoms and escalate to difficulty in breathing; widespread blisters that ooze plenty of fluid; and swelling of the face, eyes, mouth, neck, and even the genitals.
In uncommon scenarios, like a forest fire, poison oak is burned. This causes the urushiol oil to attach itself to smoke particles, causing more widespread damage. Exposure to the smoke can still cause skin rashes. Even worse, breathing in the smoke can cause harm to your lungs.
4 What are the symptoms of a poison oak rash?
Poison oak rash has a number of symptoms. These include:
Appearance of red streaks
General redness of the skin
Hives, which could be large raised areas of skin or small bumps
Similar to poison ivy, a poison oak plant has three leaflets, with the stem of the main leaflet longer than the other two. What makes poison oak distinguishable from poison ivy is its lobed leaves. The middle leaflet is evenly lobed, while the other two leaflets are irregularly lobed.
What makes poison sumac different from the other two poisonous plants isn't just its form, but also its leaflets. It consists of seven to thirteen leaflets, arranged in pairs, and there is one lone leaflet at the end of the stem.
Should I see a doctor if I have been affected by poison oak? Because the rash does not immediately manifest upon contact, diagnosing poison oak rashes might be difficult. In order to correctly discern whether the rashes you are experiencing is actually due to poison oak, it would be best to consult your doctor. This is especially true if you have never encountered such a rash before, and if you have no prior experience to compare the current condition to.
The following factors will be considered by the doctor in order to correctly diagnose your condition.
When you could possibly have been exposed to the plant. Perhaps you went on a hiking trip in the recent past?
How long it took the rash to develop
Other rashes you may have encountered in the past
Your lifestyle, such as outdoor activities, hobbies, and work information
First and foremost, it is important to resist the urge to scratch. Although the rash will never spread through the blister fluid, scratching with dirty hands and nails increases the risk of bacterial infections.
When you get a rash and automatically reach for usual remedies, it may seem like common sense, but actually, you should avoid topical antihistamines. Common antihistamines, like Benadryl cream, gel, and spray, may cause additional allergic reactions that may complicate your condition unnecessarily. The same is true for anesthetics containing benzocaine.
For mild cases of allergic contact dermatitis, you may use over-the-counter hydrocortisone creams or gels. Some popular brands include Caldecort, Cortaid and Lanacort. These help relieve itching. Medication should be applied after the rash has been soaked in water or after a compress has been applied.
However, it is important to note that this type of treatment is not advisable for severe cases of allergic contact dermatitis. It will not be effective in relieving the symptoms. This may cause some temporary reprieve from the symptoms, but it may ultimately cause the rash to suddenly flare up and worsen.
If the rash develops oozing blisters, there are simple medications that can help dry them out. These include aluminum hydroxide gel, zinc oxide, zinc acetate, zinc carbonate and kaolin.
For more severe cases, consultations with a doctor is necessary. He or she is likely to prescribe corticosteroids. But this is a prescription medicine, so you should really visit a doctor before you purchase any medication.
6 Home remedies for poison oak rash
There are also home remedies you can try to relieve the itchiness of poison oak rashes.
The first and easiest remedy is simply water. Soak the affected area in cool water for 15 to 30 minutes several times a day. This helps relieve the itching, hydrate your skin, and remove the toxins from the urushiol oil. This may be done for one to four days, or until the symptoms of itching and blistering improve. If you are at work or in any other situation where soaking the area is inconvenient or impossible, wet compresses can be used as a substitute.
You can also add baking soda or vinegar in the soak or wet compress. Baking soda can be mixed into water for a paste-like texture, and this can be applied on the rash. Allow it to dry.
Taking short cool baths will also help relieve the rash and itching. You can take baths with oatmeal additives like Aveeno. But make sure to use gentle soaps and avoid harsh chemicals. Examples of gentle soaps are Basis, Dove, Cetaphil and Oil of Olay. Keep your skin cool and moisturized. Dry skin causes the rash and blisters to worsen.
While your skin is damp, apply a moisturizer or a calamine lotion. If going for the latter option, make sure to watch the area closely for excessive drying. Calamine lotion can cause drying when used for extended periods of time.
7 Poison oak prevention
If you are going to an area that is likely to have poison oak plants, taking some precautions may save you all the trouble of dealing with poison oak rashes. Choose to wear long pants and long-sleeved shirts. Wear closed shoes as well. This will help prevent the oil from coming in direct contact with your skin. If you will be gardening and using your hands, wear vinyl or leather gloves. Rubber, latex, wool and cotton gloves will be useless against the toxic effects of urushiol oil.
You can also use barrier creams or lotions that contain bentoquatam. An example of this is IvyBlock. This can act as a barrier between the oil and your skin, so that you don’t develop rashes or at least not as severe rashes.
Afterwards, take your protective layers of clothing and wash them well. This ensures that even if your clothing got in contact with poison oak, it will not be transferred to your skin. If you suspect that there is plenty of urushiol oil on your clothes, throwing them away may also be an option.
If during your trip outdoors, you fear you may have been in contact with a poison oak plant, it’s not too late. Wash your skin right away. Use plenty of water and mild soap, an easy option is dishwashing liquid. Otherwise, if water and soap is not readily available, you can also use rubbing alcohol. Rinsing should be done often though. Soap and rubbing alcohol can cause dryness if left too long on the skin. This would make the rash worse. You should also use a brush to clean under your nails.
8 How long does poison oak rash last?
The rash lasts 10 days to three weeks. In very severe cases, allergic contact dermatitis can last up to six weeks. Succeeding exposures to poison oak may induce allergic reactions faster than the previous one. This varies from person to person as our diverse physiologies react differently. Some people can be more susceptible or more allergic to urushiol oil.
In fact, there is a very small percentage of people who are not allergic to this unique oil. Four out of five people will be susceptible to allergies, but there is still one in every five that are not harmed at all. However, if you’ve been exposed to poison oak a few times and did not develop an allergic reaction, do not rejoice just yet. Exercising caution is still necessary. As your exposure to poison oak increases, so does your chance of contracting allergic contact dermatitis.
9 Is poison oak rash contagious?
No, poison oak rash is not contagious. You cannot get the rash by touching someone with the rash, or by coming into contact with the blister fluids.
The rash is contracted and spread only through the oil itself.
10 Where is poison oak located?
It is largely distributed in western North America, including California, Nevada, Washington, Oregon, and British Columbia. It inhabits conifer, mixed broadleaf forests, grasslands, woodlands, and chaparral biomes.
11 Poison oak benefits and uses
However, far from a true villain, poison oak is also quite useful. It was once used by Native Americans in medicinal applications. The sap cures ringworm. The poultice of fresh leaves are applied to bites of rattlesnakes. The soot is an effective black dye used for tattoos and sedge basket elements. Its plant stems and shoots were also used to make baskets. But in order to harness its many useful qualities, knowledge on proper handling of the plant is very important.
12 Poison oak vs. poison ivy
First, we will explore the differences between poison oak and poison ivy in terms of geography. Poison oak plants are commonly found in the western part of North America, but another type of poison oak is found in eastern United States. In comparison, poison ivy plants are abundant on the east coast of the United States, but also in the Midwest, and some western and southern states. However, there is another variation of the poison ivy plant that grows nearly everywhere in the continental U.S. Poison ivy can be found pretty much everywhere in North America, stretching even to Canada and down the mountainous terrain of Mexico. The only exception is California and a couple of southeastern states.
Second, we will look at the difference between the habitats of the poison ivy and the poison oak plants. Poison ivy thrives in wooded areas, but can also grow in exposed rocky areas and even open fields in disturbed regions. Although it can survive in different soil types, it is often found in brackish water. By contrast, poison oak plants usually prefer damp, semi-shady areas near running water. However, some poison oaks have also been found in sunny and open areas.
Next of their differences is their appearance. Poison oak can be seen in various forms, from vines to shrubs. It is very good at blending in with the other plants, so it is not easy to spot. It mimics the size and shape of its neighboring plants. There is some similarity between poison oak and poison ivy when it comes to appearance, in that the poison ivy can also be found as a rope-like vine. They both have three leaflets. The only difference is, poison ivy will have teeth-like features along the edge of its leaves, and poison oak will have smooth edges along its lobed leaves.
Poison oak produces yellow-green and white berries. On the other hand, poison ivy grows green or yellow flowers, and its berries can be yellow-green, white or amber in color.
Both poison oak and poison ivy carry the toxic oil urushiol. So if you come in contact with either of the two plants, the rash may look the same. If you come in contact with both plants, the rashes will be indistinguishable.
Thankfully, being unable to identify whether the rash is from poison oak or poison ivy is not much of a big deal. Because they result from the same substance, urushiol oil, the treatment and even the practical home remedies that would work on poison oak rashes will also be just as effective on poison ivy rashes.
13 Poison oak vs. poison sumac
The most obvious difference between poison oak and poison sumac is the number of their leaves. Poison oak usually has three leaflets per cluster, whereas poison sumac has seven to 13 leaves on a branch. In fact, among poison oak, ivy, and sumac, it is poison sumac that really looks different. While poison ivy and poison oak both have vine and shrub variants, poison sumac appears as fern-like shrubs, but poison sumac can also grow into big trees.
Aside from their leaves, poison sumac typically has a reddish stem and glossy pale yellow or cream-colored berries. It is also commonly found in bogs and swamps throughout the east coast, parts of the Midwest, and a few southern states. In fact, there are only two states in the United States that are completely safe from poison sumac. Those are Alaska and Hawaii.
Do note that there are staghorn sumac and winged sumac plants, and these are not poisonous. Compared to poison sumac, staghorn sumac can be distinguished by its berries, which are packed close together and stand upright, whereas the berries of a poison sumac would hang low. In addition to that, the leaves of a staghorn sumac have saw-toothed edges, unlike those of poison sumac which are smooth-edged. On the other hand, winged sumac has little leafy growths, or “wings”, along the stem, between the actual leaves.
Like in poison oak, urushiol oil is also the active substance that triggers rashes when a person comes in contact with poison sumac. When you develop allergic contact dermatitis, it is nearly impossible to distinguish the rashes if they are from poison oak or poison sumac. But because these rashes do come from the same substance, the same medications and home remedies work on rashes from both plants.
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